cell-click

This generic function is called when a cell in a grid-widget is clicked. cell-click methods allow
the user to initiate arbitrary actions by clicking in particular
cells. Often the action is to prompt the user in some way for a new
value for the clicked cell; a cell-click method may then call
write-cell-value
to write the new value into the application's domain data.

If a particular grid cell is to respond to mouse clicks, and the click
is not handled by one of the built-in grid-column types such as
combo-box-column-mixin, then the
application must supply a cell-click method for cells of that
row and column type.

grid-widget, row-section,
column-section, row, and
column are the grid, grid sections, and grid
subsections that contain the grid cell that was
clicked. row-number and
column-number are non-negative integers that
indicate the sub-row or sub-column that was clicked when the
subsection is replicated (due to having a section-count property that is
greater than one); zero indicates the first subsection, and these
numbers are always zero for non-replicated subsections.

x and y are the clicked
position within the cell, where zero, zero indicates the upper left
corner of the cell (inside the borders). The various
...-border-p arguments are
true if the click was within *grid-border-mouse-slack* of the
right or bottom border of the particular section or subsection.

If trigger-key is true, this
indicates that an actual mouse click was not done, but rather that a
special key was pressed to emulate a mouse click with the keyboard. In
particular, cell-click is called when the user
presses the ENTER key or the SPACE bar (unless the user is in a
special mode such as typing into an editable-text-column-mixin
cell). trigger-key is then the integer code of
the key that was pressed, and is therefore the value of either vk-return or
vk-space.

A cell-click
method could respond differently to each of these keys; for example, a
combo-box-column-mixin cell will
drop its choice list when SPACE is pressed, as if the user clicked on
the cell's arrow, but will start a text edit when ENTER is pressed
(assuming that the column's typable property is on), as if the
user clicked in the text area of the cell.

Copyright (c) 1998-2012, Franz Inc. Oakland, CA., USA. All rights reserved.Documentation for Allegro CL version 9.0. This page was not revised from the 8.2 page.Created 2012.5.30.